Today’s first glitch:
Apostrophes aren’t for plurals (almost all the time), but they are for possessives (except pronouns, of course). Unless you intend to say this character has more than one mind, you need an apostrophe before the s in minds. (Even if you do intend to say that, you need an apostrophe, just after the s instead of before it, but why do the multiple minds have only one eye between them? *shakes head*)
There’s a typo, too. Did you catch it?
Do not use an em dash where there is neither an abrupt change in direction or an interruption. Replace the dash after motherly with either a colon (in the “more information/explanation follows” usage) or a comma.
As it is used in this example, however is an interrupter. Interrupters need to be separated from the rest of the sentence with commas (or only one comma if it falls as the first or last word). Add a comma before however.
When referring to words as the words themselves, use italics, not quotation marks. Get rid of the single quotes around Lady Manure and Lady Muck (notice the corrected capitalization!) and italicize these instead.
In her mind’s eyes, she was helpful and motherly: the perfect neighbor. The locals, however, saw her as a nuisance and a meddler, and dubbed her Lady Manure, or Lady Muck for short.